About Transaction objects
Contents
In a PowerBuilder database connection, a Transaction object is a
special nonvisual object that functions as the communications area between
a PowerBuilder application and the database. The Transaction object
specifies the parameters that PowerBuilder uses to connect to a database.
You must establish the Transaction object before you can access the
database from your application, as shown in the following figure:
Figure: Transaction object to access database
Communicating with the
database
In order for a PowerBuilder application to display and manipulate
data, the application must communicate with the database in which the data
resides.
To communicate with the database from your PowerBuilder
application:
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Assign the appropriate values to the Transaction object.
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Connect to the database.
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Assign the Transaction object to the DataWindow control.
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Perform the database processing.
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Disconnect from the database.
For information about setting the Transaction object for a
DataWindow control and using the DataWindow to retrieve and update data,
see DataWindow Programmers Guide.
Default Transaction object
When you start executing an application, PowerBuilder creates a
global default Transaction object named SQLCA (SQL Communications Area).
You can use this default Transaction object in your application or define
additional Transaction objects if your application has multiple database
connections.
Transaction object
properties
Each Transaction object has 15 properties, of which:
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Ten are used to connect to the database.
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Five are used to receive status information from the database
about the success or failure of each database operation. (These
error-checking properties all begin with SQL.)